OBJECTIVE To develop a systematic analytical approach using ultra high performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS), so as to comprehensively elucidate the chemical compositions and multi-part differential characteristics of various parts, including roots, stems, and leaves of the She ethnic medicine Xiaoxianggou.
METHODS Precise molecular weights and multi-stage fragment ion information were acquired via dual-mode scanning of positive and negative ions. Through comparison with reference substances, retrieval of relevant literature, and search in the PubChem database, multi-dimensional data cross-validation was realized. Pareto scaling data pre-processing was employed. Principal component analysis(PCA) and partial least squares-discriminant analysis(PLS-DA) were utilized for multi-group analysis of different botanical origins and various parts of Xiaoxianggou. Subsequently, orthogonal partial least squares-discriminant analysis(OPLS-DA) was applied for multivariate statistical analysis of 3 combinations of parts, namely roots and leaves, stems and leaves, as well as roots and stems. Chemical components with significant differences in Xiaoxianggou from different parts were screened based on a variable importance in projection value greater than 1 and a P-value less than 0.05.
RESULTS A total of 63 compounds were identified, encompassing flavonoids, coumarins, terpenoids, organic acids, esters and other compound categories. Twenty-three compounds, such as quinic acid and 3-hydroxy-2-methoxyphenol-1-O-β-D-glucuronic acid, were first discovered in this plant. The differential compounds among the roots, stems, and leaves predominantly consist of flavonoids, organic acids, and coumarins.
CONCLUSION This study has preliminarily identified the chemical constituents of the roots, stems, and leaves of Xiaoxianggou and uncovered the distribution patterns of their differential constituents, offering a reference for subsequent basic research on the material basis of pharmacological effects and the development of quality standards.